The Ocean in the Aeolotron: Final SOPRAN laboratory experiment

On October 6, several groups from the SOPRAN project met in Heidelberg to discuss the measuring program of the final SOPRAN laboratory experiment at the Heidelberg Small-Scale Air-Sea Interaction Facility, the Aeolotron.

The focus will be on the first air-sea gas exchange measurements with seawater from the Atlantic Ocean in the Aeolotron, including the effects of the natural surface micro layer and bubbles. In addition, aerosols will be sampled with different techniques to investigate to what extent organic material from the sea surface micro layer (SML) is carried into aerosol. The experiments will also be essential for the provide further experimental data for the new SOPRAN air-sea gas transfer model with conditions, where data are not yet available.

The participating groups are J. Williams, MPI for Chemistry, Mainz (PTR-MS measurements of gas concentrations in air and water), A. Engel, GEOMAR Helmholtz Centre for Ocean Research Kiel (SML measurements), M. van Pinxteren, TROPOS (aerosol measurements), and B. Jähne, U. Heidelberg (MIMS and FTIR gas exchange measurements, active and passive thermography, and all environmental parameters including wave slope imaging). External groups include O. Wurl, ICBM (CO2 gas exchange and SML measurements), B. Schneider, IOW (CO2 measurements), and foreign groups from England (J. Najera, U. Manchester) and France (B. D'Anna, CNRS, lab IRCELYON). The latter two groups will support the aerosol measurements. The experiment will take place from November 3 until 28, 2014. On September 23, twenty tonnes of Atlantic seawater, sampled from the Northern Atlantic Ocean on board of the research vessel POSEIDON and reloaded to a road tanker at GEOMAR, arrived in Heidelberg and were filled into the storage tanks in the basement of the building, where the Aeolotron is located.

Fig.1: The Aeolotron at the Heidelberg Institute of Environmental Physics